Apparatus and method for automatically milking animals

ABSTRACT

A method and apparatus for automatically milking animals such as cows which includes one or more milking compartments, each milking compartment having a milking robot including teat cups which are supported by a robot arm member. A detector that generates beams and uses their reflections for determining the position of the teats of an animal in a milking compartment is disposed on a robot arm construction spacially separated from the robot arm member. The robot arm construction is maneuverable up and down and side-to-side and is mounted so that its beams can scan the animal&#39;s teats from different directions. The milking robot is capable of connecting the teat cups to the animal&#39;s teats selectively simultaneously or non-simultaneously and automatically uncoupling the teat cups from the animal&#39;s teats either simultaneously or non-simultaneously.

RELATED APPLICATION

This Application is a Divisional Application of application Ser. No.08/596,360 filed Mar. 4, 1996, a national stage of PCT/NL95/00230, filedJun. 29, 1995, which issued as U.S. Pat. No. 5,784,994 on Jul. 28, 1998.

FIELD OF THE INVENTION

The present invention relates to an apparatus for automatically milkinganimals, such as cows, which includes milking compartments havingmilking robots for automatically connecting teat cups to the teats ofthe animals. In particular, the invention relates to an apparatus ofthis type which further includes a detector for determining the positionof the teats.

SUMMARY OF THE INVENTION

Types of such apparatus are known but do not always work satisfactorily.The invention has as an object to improve types of apparatus of thisnature. The apparatus is improved in that the detector is constructed insuch a manner so that the detector's beams will be at different angleswith respect to the teats of the animal to be milked. The invention alsorelates to an apparatus for automatically milking animals, such as cows,having one or more milking compartments which include one or moremilking robots for automatically connecting teat cups to the teats ofthe animals and, in combination, further include a detector fordetermining the position of the teats, wherein the detector is arrangedfor performing a scanning motion in different directions. In thissituation, the scanning beam of the detector can be positioned so thatit can move up and down and to and fro. To make it possible to detectteats which are located at different heights above the floor of themilking compartment, the detector can perform a scanning motion throughat least five centimeters, and preferably through approximately tencentimeters in the vertical direction. More in particular, forperforming this motion in the vertical direction, the detector can beconnected through the intermediary of a four-bar linkage to a robot arm.Apart from a movement in the vertical direction, the detector is alsocapable of rotation in a generally horizontal plane. To that end, thedetector can be connected so as to be capable of rotating around asubstantially vertical axis relative to the robot arm. The robot arm ispreferably attached to a side of a milking compartment or arrangedclosely thereto. The robot arm is designed so that the detector can bemoved to outside the milking compartment.

When the detector becomes contaminated, this may be to the detriment ofthe accuracy with which the position of the teats is determined, and itis possible that a positional determination cannot be made at all. Tosolve this problem, the apparatus may be fitted with a cleaning memberfor cleaning the detector. The invention, therefore, also relates to anapparatus for automatically milking animals, such as cows, having one ormore milking compartments and one or more milking robots forautomatically connecting teat cups to the teats of the animals, infurther combination with a detector for determining the position of theteats and a cleaning member for cleaning the detector. This cleaningmember is preferably arranged outside the milking compartment, andconnected with the side framework of the milking compartment. More inparticular when the detector comprises a laser, it has a window whichcan get dirty. For that reason, the cleaning member may be provided withspraying or blowing means or both for spraying a cleaning liquid orblowing air, respectively, against the window, thus cleaning the window.This cleaning operation may be effected after each milking turn; thefrequency of cleaning the window may be lower when it is found that thewindow is contaminated less frequently.

The motion of the component parts of the robot arm and the motion of thedetector can be performed by means of computer-controlled steppingmotors. Both for this function and in general for controlling the entiremilking procedure and the procedure of automatically connecting anddisconnecting the teat cups, a computer is used.

The apparatus further includes an animal identification system connectedto this computer, the computer having stored in it a control programadapted to the individual animals for moving the detector to ananimal-specific position under the udder. The position from which thedetector can detect in the most accurate manner the position of theteats of the animal, depends on the position of the teats and willconsequently depend on the physiological characteristics of individualanimals. After the position of the teats has been determined, the teatcups can be connected. The apparatus is arranged so that optionally thefour teat cups can be coupled simultaneously or one after the other tothe teats of an animal. The teat cups are uncoupled from the teatsindividually. The invention, therefore, further relates to a method ofautomatically milking animals, such as cows, using a milking robot withteat cups, in which the four teat cups are automatically coupledsimultaneously or one after the other to the teats of an animal, whilethe teat cups can also be coupled individually.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the invention and to show how the same maybe carried into effect, reference will now be made, by way of example,to the accompanying drawings, in which:

FIG. 1 is a side elevational view of a milking compartment in accordancewith the invention with a cow shown therein in dashed lines;

FIG. 2 is a rear elevational view of a milking robot, a teat cup beingconnected to a teat of an animal shown in dashed lines standing in themilking compartment;

FIG. 3 is a rear elevational view of the milking robot, wherein the teatcups are connected to the teats of an animal shown in dashed lines inthe milking compartment and wherein the robot arm is thereafterretracted to outside the milking compartment;

FIG. 4 is a plan view of the milking compartment with the milking robot,wherein all four teat cups have been connected to the teats of an animalwhich is shown in dashed lines standing in the milking compartment andwherein the robot arms have thereafter been retracted to outside themilking compartment;

FIG. 5 is a side elevational view of a milking compartment accommodatinga cow, of which the front and rear teats are at unequal heights, and inwhich figure a detector is shown in the position in which it candetermine the location of the rear teats; and

FIG. 6 is a plan view of the milking compartment shown in FIG. 5containing the detector, and illustrating the manner in which it ismovable and cleanable.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows, in a side elevational view, a milking compartment 1 inwhich a cow to be milked is present. Milking compartment 1 includes aframework 2 which surrounds the milking compartment at all four sides,an entrance door 3 at the rear side and two exit doors 4 and 5 havingbeen arranged in the compartment's framework at the two longitudinalsides (see FIG. 4). Via one of these exit doors the animal can beconducted from the milking compartment to a shed area or a pasture,while via the other door the animal can be conducted to a specialisolation area, e.g. because mastitis has been detected during milking.The entrance and exit doors are under the control of a computer system,not shown. At the leading side of milking compartment 1 a feeding trough6 has been disposed, which is part of an automatic feeding system. Theanimals to be milked wear a collar 7, which is equipped with atransponder 8 that cooperates with a sensor 9 disposed at or nearfeeding trough 6. When an animal enters milking compartment 1 and hasadvanced sufficiently that it can put its head into feeding trough 6,the distance between transponder 8 and sensor 9 is such thatcommunication between the two elements 8 and 9 occurs. Transponder 8 andsensor 9, which is connected to the computer system, constitute ananimal identification system. As soon as communication betweentransponder 8 and the sensor 9 becomes possible, the animal isidentified and a file stored for this animal in the memory of thecomputer system becomes accessible, which file includes various data,such as data for the automatic supply of food, the automatic connectionof the teat cups and the subsequent automatic milking operation and formonitoring the health condition of this animal.

After the animal has entered milking compartment 1 and has beenidentified therein, a detector 10, here in the form of a laser detector,is moved to under the animal. In the FIGS. 1 and 4, detector 10 isdisposed on a robot arm system 11, formed by robot arms 15 and 16 whichare pivotal about cylindrical vertical shafts indicated by referencenumerals 12 and 13, this robot arm system 11 being attached to framework2 in such a manner that it is pivotal about shaft 13. Robot arms 15 and16 are pivotal with the aid of computer-controlled motors 37 and 38, forwhich stepping motors are preferably employed. Using detector 10, theposition of the teats relative to milking compartment 1 can bedetermined, whereafter teat cups 18 can be fitted on the teats. Detector10 and the means for fitting teat cups 18 to the teats together form amilking robot. In the embodiment shown, these means include a separaterobot arm construction 19 for each of the teat cups 18. Such a robot armconstruction 19 includes a first four-bar parallelogram linkage 20, withthe aid of which a vertical carrier 21 is connected which is capable ofmoving in vertical directions relative to frame portions 22 of framework2. The pivotal shafts, by means of which this four-bar linkage isconnected to the frame portions, are denoted by reference character 20A.At the lower side of carrier 21 there is a second four-bar parallelogramlinkage 23, with the aid of which a robot arm 24 is movable from outsidethe milking compartment 1 into the milking compartment to under ananimal present therein and can again be retracted to outside the milkingcompartment. This robot arm 24 is furthermore pivotal about a verticalshaft indicated by reference numeral 25 relative to carrier 21. Each ofrobot arms 24 acts as a carrier for one or more teat cups 18. By meansof first and second four-bar linkages 20 and 23, respectively, and thepivotal construction about shaft 25, teat cup 18 connected to robot arm24 can be moved omnidirectionally. In the embodiment shown, the pivotalmotion of robot arm 24 relative to shaft 25 is provided by acomputer-controlled motor 14, the reciprocal motion of robot arm 24relative to carrier 21 by a computer-controlled motor 17, while theup-and-down motion is provided with the aid of the first four-barlinkage by a computer-controlled operating cylinder/piston combination41, preferably a pneumatic cylinder/piston combination. Motors 14 and 17are preferably stepping motors.

A teat cup 18 is connected to a corresponding robot arm 24 by means of aflexible element, such as a cord 26, which cord is not only connected toa teat cup 18 but also to an operating cylinder/piston combination,preferably a pneumatic cylinder/piston combination, accommodated in eachrobot arm 24. If, as is shown in FIG. 2, a teat cup 18, carried by robotarm 24, is fitted on a teat, then, as soon as teat cup 18 has been drawnonto the teat with the aid of the vacuum produced therein, thecylinder/piston combination accommodated in robot arm 24 is activated toextend cord 26, robot arm 24 is retracted to outside milking compartment1 and teat cup 18 remains connected to robot arm 24 only loosely by cord26 and will, therefore, have a sufficient freedom of movement to trackthe animal's movements. In this situation, it may happen that teat cups18 are inhibited in their free motion capability by milk tubes 27 andpossibly by pulsation tubes 28, more in particular when these tubes havebeen secured to the robot arm construction 19. It is, therefore,advantageous for tubes 27 and 28 to move as freely as possible and nothamper teat cups 18 when they follow the animal's movements. To thatend, tubes 27 and 28 connected to teat cups 18 extend during milking, asseen in plan view, from the teat cups to which these tubes areconnected, obliquely forwardly in the direction that the animal facesand outwardly and thereafter the tubes loop farther outwardly andrearwardly (see FIG. 4). From the teat cups tubes 27 and 28 thus extendoutwardly on both sides of the milking compartment and back along eachside of the milking compartment. The tubes extend generally in a "U"shape to points of connection 29, provided at the side of the milkingcompartment to receive tubes 27 and 28. The loop-shaped arrangement ofthe tubes increases the free motion capability of the teat cups. Thefurther milk lines and vacuum lines of the milking system are connectedin the same manner to their respective points of connection. Because tworobot arm constructions 19 are disposed on both sides of the milkingcompartment 1, only one point of connection 29 is sufficient for eachside. Of course, alternatively there may be a point of connection fortubes 27 and 28 of each robot arm construction. Since the robot arms 24are movable from outside the compartment obliquely rearwardly andinwardly to under the animal, the tubes 27 and 28 first extend from acorresponding teat cup approximately in the same direction as in whichthe relevant robot arm 24 is disposed, whereafter the tubes curvetransversely and rearwardly underneath the robot arm to the relevantpoint of connection 29. Because between teat cups 18 and points ofconnection 29 the tubes are not connected to anything else, they canmove freely near the milking compartment floor. Consequently, theyoccasion only slight resistance and do not to any significant extentobstruct the motion of the teat cups. When the teat cups have beenconnected to the teats, then the tubes 27 and 28 generally extend in ahorizontal plane and the tubes are movable in this plane (see FIG. 3).When the teat cups are to be uncoupled, then, because of the fact thatthe robot arms have been moved to outside the milking compartment duringmilking, these robot arms must first be moved towards the teat cups,while simultaneously or shortly thereafter the operating cylinder/pistoncombinations in robot arms 24 are energized in order to retract cords 26and pull the teat cups up against the holder at the end of robot arm 24.Since there are four robot arm constructions 19 which operateindependently of each other, the teat cups can be coupled simultaneouslyor one after the other and independently of each other to the teats ofan animal. Also uncoupling of a teat cup can be effected independentlyof the other teat cups.

When, after the milking operation has ended, a teat cup 18 has beenpulled up against a relevant robot arm 24 and this arm has thereafterbeen returned to its position of rest outside the milking compartment,the teat cup can be automatically cleaned in this rest position. To thatend (see FIGS. 1 to 3), spray heads 42 connected to a washing circuit(not shown) are positioned at or near both sides of the milkingcompartment. Teat cups 18 are connectable independently of each other tothese spray heads 42, more in particular when robot arms 24 carryingteat cups 18 have been moved to their position of rest.

In contrast to the cow standing in the milking compartment shown in FIG.1, the cow in the milking compartment shown in FIG. 5 has teats whichare at unequal heights. It regularly happens that cows have teats whichare located very closely next to each other or are at different heightsor both. Because of the advantageous construction of a separate robotarm structure for detector 10 in accordance with the invention, itbecomes possible to determine the position of such teats. Such a robotarm structure for detector 10 is illustrated in FIGS. 5 and 6. The meansfor the connection of the teat cups have been omitted from thesedrawings. Detector 10 is located on a robot arm structure 30, which isof such a design that the detector is omnidirectionally or substantiallyomnidirectionally movable in the milking compartment. Detector 10 isconnected via a four-bar parallelogram linkage 31 to a robot arm 32,which is part of the robot arm structure 30. Robot arm 32 is pivotalabout a vertical shaft indicated by reference numeral 33, arranged atthe side of milking compartment 1. Four-bar linkage 31 is connected soas to be capable of pivoting about a vertical shaft indicated byreference numeral 34 to robot arm 32. Detector 10 is further connected,capable of pivoting about its own longitudinal shaft indicated byreference numeral 35, to four-bar linkage 31 (see FIG. 5). Because ofthe feature that it is pivotal about the shafts 33, 34 and 35 and thefeature that it is movable in height with the aid of the four-barlinkage 31, detector 10 can move around the teats in all positions andmore particularly always to a position that the teats can be detected,whatever their positions relative to each other may be. Four-bar linkage31 and the pivotability of detector 10 about its own longitudinal shaft35 makes it possible for the detector to effect a scanning motion indifferent directions, so that teats differing from normal teats can bedetected. The scanning motion in the upward direction can then beeffected through at least approximately five centimeters and canpreferably amount to approximately ten centimeters in the verticaldirection. Should there be animals of which the difference in heightbetween the front and rear teats of the udder is still larger, then thepivotal motion can be adapted thereto.

In the present invention, the detector is constituted by a laserdetector and positioned as such in a housing having a window, throughwhich the laser beam is transmitted. When this window gets dirty, thedetection of the teats may not be sufficiently accurate. It is,therefore, important to provide the apparatus with means, with whichdetector 10 can be cleaned. To enable cleaning in an efficient manner,the pivotal motion about shafts 33 and 34 is such that detector 10 canbe moved to outside milking compartment 1 to a cleaning position, asindicated by broken lines in FIG. 6. In this position, the detector canthen be cleaned using a cleaning member 36 provided for that purpose.This cleaning member 36 may include spraying or blowing means or bothfor spraying a cleaning agent or blowing air or both against the windowof detector 10, respectively.

Performing the pivotal motions about shafts 33 and 34 and a motion invertical directions by means of four-bar linkage 31, as well as therotation of detector 10 about its own longitudinal shaft, are monitoredby computer-controlled motors, preferably stepping motors 37, 38, 39 and40. Although in many cases the detector can be placed in a fixed workingposition, shown in FIG. 6, it may sometimes be necessary for detector 10to be operative in a plurality of positions to enable a determination ofthe position of the various teats. Thus, it may be necessary fordetector 10 to be arranged for the determination of the position of thefront teats in a first working position in the midway point between andbefore the leading teats, whereas for the determination of the positionof the trailing teats the detector must be placed in a position fartherto the rear. It may alternatively be possible that the detector shouldnot be arranged in the midway point between the teats, but more to theside; the latter will more specifically be the case when one teat wouldbe in the shadow of the other teat relative to the detector or when twoteats are very close to each other. Since the relative position of theteats of the several animals is known, this can be taken into account onarranging the detector in the working position under the animal. Thecomputer system may include a control program adapted to the individualanimals for moving the detector to an animal-specific position under theudder, which control program can be addressed with the aid of the animalidentification system for the relevant animal. This animal-attunedcontrol program can be triggered on the basis of data present in thecomputer system in the data file for each animal. Detector 10consequently has a position of rest (indicated by broken lines in FIG.4), as well as a cleaning position (see FIG. 6) and one or more workingpositions adapted to the individual animals.

The invention is not limited to the embodiments disclosed herein, butalso extends to modifications which would occur to a person skilled inthe art and which are within the scope of the following claims:

I claim:
 1. A method of automatically milking an animal, such as a cow,using a milking robot which includes teat cups, the method comprisingautomatically and simultaneously coupling the teat cups to the animaland automatically decoupling said teat cups individually andnon-simultaneously from the teats of the animal, whereby the teat cupsare individually uncoupled.
 2. A method of automatically milking ananimal such as a cow, using a milking robot which includes teat cups,the method comprising automatically coupling teat cupsnon-simultaneously to the animal's teats and subsequently automaticallydecoupling said teat cups from the animal's teat simultaneously.
 3. Amethod of automatically milking an animal such as a cow using a robothaving four robotic arms each of which supports a teat cup which isconnected thereto via an extendable flexible member, said robot furthercomprising a detector for locating the positions of the animal's teats,said detector being disposed on a robot arm construction spaced fromsaid robotic arms, the method comprising the steps of: locating thepositions of said animal's teats by moving said robot arm constructioninto the vicinity of said teats and detecting their positions by saiddetector; moving said robot arm construction with said detector disposedthereon so that said detector is spaced and separated from said roboticarms and the teat cups supported thereby, said robot arm constructiontogether with said detector being omni-directionally moved in thevicinity of said teats while generating beams from said detectordirected at different angles towards said teats and determining thepositions of said teats from the reflections of said beams;automatically coupling said teat cups to the animal's corresponding saidteats at their respective positions as determined by the reflections ofsaid beams; withdrawing said robotic arms from said teat cups whilemaintaining a connection between said teat cups and their respectiverobotic arms by the extendable flexible members; and automaticallyuncoupling said teat cups from said teats and withdrawing said teat cupsto their corresponding robotic arms by moving them thereto by saidextendable flexible members as the milking of the animal is concluded.4. A method in accordance with claim 3 wherein said step of couplingsaid teat cups to corresponding said teats is accomplished by saidrobotic arms substantially simultaneously and said step of uncouplingsaid teat cups from said teats by moving said teat cups to theircorresponding robotic arms by said extendable flexible members is notaccomplished simultaneously.
 5. A method in accordance with claim 3,wherein the coupling of said teat cups to corresponding said teats bysaid robotic arms is not accomplished simultaneously and wherein theuncoupling of said teat cups from said teats by moving said teat cups tosaid robotic members by said extendable flexible members is accomplishedsubstantially simultaneously.
 6. A method of automatically milking ananimal such as a cow, using a robot having four robotic arms each ofwhich supports a teat cup and is connected thereto via an extendableflexible member, said robot further comprising a detector for locatingthe teats of the animal which is disposed on a robot arm constructionspaced from said robotic arms, the method comprising the steps of:locating the positions of the teats of said animal by moving said robotarm construction into the vicinity of said teats and detecting theirrespective positions by said detector; moving the teat cups by saidrobotic arms to under their positions as determined by the detector;automatically and simultaneously coupling said teat cups tocorresponding said teats; withdrawing said robotic arms from said teatcups while retaining connections between said teat cups and theirrespective said robotic arms by the extendable flexible members; andautomatically uncoupling said teat cups non-simultaneously from saidteats and withdrawing said teat cups to their corresponding said roboticarms by said extendable flexible members as a milking of said animal isconcluded.
 7. A method of automatically milking an animal such as a cowusing a robot having four robotic arms each of which supports a teat cupand is connected thereto via an extendable flexible member, said robotfurther comprising a detector for locating the teats of the animal whichis disposed on a robot arm construction spaced from said robotic arms,the method comprising the steps of: locating the positions of the teatsof said animal by moving said robot arm construction in the vicinity ofsaid teats and detecting their respective positions by said detector;moving the teat cups by said robotic arms to under their respectivepositions as determined by said detector; automatically andnon-simultaneously coupling said teat cups to their corresponding saidteats; withdrawing said robotic arms from said teat cups while retainingconnections between said teat cups and their respective robotic arms bythe extendable flexible members, and automatically uncoupling said teatscups simultaneously from said teats and withdrawing said teat cups totheir corresponding robotic arms by said extendable flexible members asthe milking of said animal is concluded.
 8. An apparatus forautomatically milking animals, such as cows comprising: a milkingcompartment, a milking robot including teat cups for being connected toan animal in said compartment, said teat cups being supported by a robotarm means; a detector that generates beams and uses their reflectionsfor determining the positions of teats, said detector being disposed ona robot arm construction spacially separated from said robot arm means,said robot arm construction comprising omni-directing means formaneuvering said detector so that said detector's beams can be aimed atdifferent angles with respect to the teats of the animal to be milked insaid compartment, said omni-directing means comprising scanning meansfor performing a scanning motion in different directions, said milkingrobot comprising means for automatically connecting said teat cups tothe teats of the animal selectively simultaneously or non-simultaneouslyand for automatically uncoupling said teat cups from the teats of theanimal selectively simultaneously or non-simultaneously.